This invention relates to a racing tire used on an oval race course, and more particularly to a racing tire for an oval race course which tire can last for a long period of time in a severe race on an oval race course.
In a race on an oval race course provided with banks in the corners and having a simple elliptic shape in plan, vehicles run at a high speed, so that the tires rotate under very severe conditions. When a vehicle runs on a bank in a corner, a load on the portion of a tire tread which is on the outer side of the race course increases greatly. This can cause separation of the belt edge of a tire tread which is on the outer side of the race course. Great wear on the region of a tread surface which is on the outer side of the race course, and even possibly a blowout can occur. Generally, a decrease in the life of the tire occurs.
To deal with these inconveniences, countermeasures are employed, such as changing the manner of setting tires on a vehicle; setting tires on the side of a vehicle which is on the outer side of a race course having an outer diameter which is larger than that of the tires set on the side of the vehicle which is on the inner side of the race course; or setting tires of a rubber material having a high abrasion resistance on the side of a vehicle which is on the outer side of the race course compared with those on the inner side of the course.
However, even when the tire setting manner and the specifications of tires to be set on the side of a vehicle which is on the outer side of a race course are changed, a load on the region of each tire tread which is on the outer side of a race course is still large. Consequently, these countermeasures may not constitute effective enough solutions.
Moreover, when different tires are set on the outer and inner sides of a vehicle which are on the outer and inner sides of a race course, and, when tires of different specifications are set on the front and rear sides of a vehicle, it becomes necessary to provide a plurality of types of tires in accordance with the tire setting positions.